Apparatus for contacting finely divided solid particles with gaseous materials



Jan.10,'1950 E EMMINGER 2,494,337

' C. H APPARATUS FORGONTACTING FINELY DIVIDED SOLID PARTICLES WITHGASEOUS MATERIALS Original Filed Sept. 12, 1941 3 Sheets-Sheet 1QEGBNIRA'HON Qua-nan \Mooas 6A5 CYcA-QN: saPAaATow. 5a 88 i {02fiamanov.

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APPARATUS FOR cou'mc'rmc FINELY nxvmzn souo PARTICLES um GASEOUSMATERIALS Original Filed Sept. 12, 1941- 3 Shepfs-Sheat 2 F I G. 2PowDeP. INLET POWDB Qu'r LET 6A5 INLET Charles E. Hcmmv'nqer Unvanbor bqMGM. or n :14

' C. E. HEMMINGER APPARATUS FOR CONTACTING FINEL SOLID PARTICLES WITHGASEOUS MATERIALS .Original Filed Sept. 12, ,1941' n v m h A a m 5 MS Iv I D V GAS Ou-r men n v Dov/0 22.

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Powsuz Oman-- Charla: E'.Hemrninger Unvenbor Qtbcprncg UNWED STATESPATENT OFFICE arrana'rus roa oox'rac'rnvo mar mvman some names wrrnGASEOUS maranms 1 Charles E. Hemmlnger, Westfleld, N. 1., asslgnor toStandard Oil Development Company, a corporation of Delaware Originalapplication September 12, 1941, Serial No. 410,525. Divided and thisapplication May 30, 1944, Serial No. 538,004

Claims. (or. 723-286) This invention relates to treating vapors or gaseswith finely divided solid contacting material and more particularlyrelates to the catalytic conversion of hydrocarbons in which finelyplate l6. Extending upwardly from the plate ll 3 are small tubes 22provided with caps 24 to prodivided catalyst material is used. videpassageways for the vapor or gas passing According to my invention,vapors and/or gases upwardly through the vessel Ill. As before arepassed through a reaction zone or vessel in a stated, the velocity ofthe vapors or gases is so direction countercurrent to the flow of flnelydiadjusted that the solid particles are maintained vided contactingmaterial. Preferably the vapors in a fluidized condition. The solidparticles in or gases are passed upwardly through the reac- 1o fluidizedcondition are shown at 26 on plate i6. tion zone and the finely dividedsolid contacting Arranged above the plate I6 is another plate 26material is passed downwardly through the rewhich is spaced from thewalls of the vessel It action zone. The velocity of the vapor or gas isas at 32 to provide passageways 33 for conductso adjusted that the solidparticles are fluidized ing the fluidized solid particles from the plate23 and simulate a liquid. 16 to the plate l6 directly beneath the plate23. The

According to the preferred form of my invention, the reaction zone orvessel is provided with contacting means whereby intimate contactbetween the solid particles and the vapors or gases is obtained.

In the drawings;

Figure 1 represents a diagrammatic showing of apparatus adapted to carryout my invention;

Figure 2 represents an enlarged detail showing the internal constructionof one form of contacting means in a vessel;

Figure 3 represents a horizontal cross-section taken substantially online III-1II of Figure 2;

Figure 4 represents another form of reaction vessel; and

Figure 5 represents a modification of the form of vessel shown in Figure4.

Referring now to the drawing, the reference character i0 designates areaction zone or vessel wherein vapors and gases are contacted withfinely divided solid material. The vapors or gases are introduced intothe lower portion of the vessel through line l2. Finely divided solidcontacting material is introduced into the upper portion of the vesselill through line H. The contacting material may be fresh or may beregenerated. The flow of the finely divided material and vapors or gasesis countercurrent in the vessel It and in order to effect intimatecontact between the solids and the vapors or gases contacting means arearranged within the vessel ill.

As shown in the drawings, the reaction zone or vessel it comprises abubble tray column. Instead of this construction the vessel to may be apacked tower or may be a disc and doughnut tower, etc. The vessel is soconstructed to providecontact between the vapors and solid particlespassing through the vessel il' Attention is directed to Figure 2 whichshows an enlarged detail of the vessel It and includes a plate I6havplate 26 is also provided with upwardly extending tubes 34 providedwith caps 36 to provide passageways for the vapors or gases passingupwardly through the vessel III while at the same 90 time preventingdownward flow of the fluidized solid particles through the tubes 34. Thesolid particles in fluidized condition are shown at 36 on the plate 23.The fluidized solid particles are conducted to the plate 28 by means ofa down spout 42 which conducts the fluidized solid partercurrentrelation to the vapors or gases.

ticles from a plate directly above the plate 26.

Beneath the first mentioned plate 16 is another plate 46 which issimilar in construction to the plate 26. Plate 46 is so arranged to havepassageways 41 for conducting the fluidized solid particles from theplate 46 to the plate 43 which is arranged beneath the plate 46. Plate43 is similar in construction to the first mentioned plate l6 and has adown spout 49 for conducting fluid ized solid particles from the plate48 to the plate directly beneath. Preferably the down spouts 42, I6 and49 extend below the surface of the fluidized mass of the solid particleson the respective plates.

From the above it will be seen that the vapors or gases pass upwardlythrough the vesrsl l6 and the velocity of the vapors or gases is soadjusted that the solid particles are fluidized and flow like a liquid.The fluidized solid particles flow downwardly in the vessel Ill in coun-For example, the upflowing vapors or gases pass through the bed 26on'plate l6 to maintain the solid particles in fluidized condition. Thefluidized solid particles'flow from the plate 16 through the down spoutl8 to the next lower plate 46. The

' vapors or gases pass upwardly through the bed of fluidized, solidparticles 26 and through tubes 34 arranged on plate 23 and then throughthe bed of solid particles 38 on the plate 23.

With the arrangement of contacting means above described. intimatecontact between the vapors or gases and solid particles is effected anda greater degree of agitation is obtained than in vessels which do nothave the contacting means. If desired, heating or cooling coils i! maybe introduced into the space between the plates. For example, in Figure2 tubes 52 are shown arranged between plates iii and ll.

In the catalytic conversion of hydrocarbons carbonaceous deposits areformed on the solid particles which are catalytic in this type ofoperation and it is usually necessary to regenerate the catalystparticles before reusing them in another conversion operation. In someinstances the catalytic particles may be recycled to the conversion zoneor vessel Iii without regeneration. The regeneration of the catalystparticles or solid particles will be hereinafter described in greaterdetail.

The reaction products in vapor iorm pass overhead through line 54. Whilethe velocity of the vapors or gases through the vessel in is relativelylow, the reaction products carry some of the solid particles overhead.It is desirable to remove these solid particles from the reactionproducts and the vapors passing through line 54 are introduced into aseparating means 56 which may be any suitable separating means but whichis shown in the drawing as a cyclone separator. More than one separatingmeans may be used if desired. In the separating means 58, vapors andgases are separated from substantially dry solid particles. The reactionproducts in vapor form pass overhead through line 58 and are furthertreated as desired to separate desired constituents. In the catalyticconvers on of hydrocarbons the reaction products in vapor forrrf'arepreferably passed to a fractionating system where the desired motorfuels are separated from the rest of the reaction products.

The separated solid particles collecting in the separator 56 arewithdrawn through line 62 and passed through line 64 having a valve 68to a regeneration zone presently to be described. In some instances itmay be desirable to recycle some of the separated solid particles to thereaction zone or vessel in by means of line II.

The contaminated solid particles which move downward in the reactionzone or vessel iii are preferably passed throu h a strippin section forremoving residual reaction products. In the catalytic conversion of hdrocarbons residual hydrocarbons are removed from the catalyst particlesin this section. If desired. heatin coils 88 may be introduced betweenthe plates in the lower sect on of the reaction zone or vessel Hi. Steamor other suitable stri ping gas is introduced into the bottom portion ofthe reaction vessel or zone in through line 12.

The strip ed solid particles are withdrawn from the bottom of thereaction zone or vessel Iii thro h line ll having a val e 18. Air orother s itable regene atin gas is introduced into line 14 below line 16by means of line I8 and the contam nated solid particles are carried insus ension throu h line 82 to a separating means 88 for separating thesolid particles from gases. The separating means 86 is anv suitableseparator and is sho n on the drawin as a cyclone separator. More thanone cvclone separator may be used if desired. The separated gases passoverhead through line 88. The separated solid articles are withdrawnfrom the bottom oi the separat ng means 86 and passed through line 92into the'top portion of a regeneration zone 93. The contaminated solidparticles from the separator 58 which are passed through line I! arepreferably mixed with the solid particles withdrawn from the bottom ofthe reaction zone or vessel l and this mixture is introduced into theseparating means 85 Just described. Line I! may pass directly into thetop oi vessel 98, eliminating the recovery means 86. The air in line 82is separated from entrained solids in separating means presently to bedescribed.

Air or other suitable regenerating gas is introduced into the lowerportion of the regeneration zone 93 through line 84. The regenerationzone I! is of substantially the same construction as the reaction zoneor vessel In above described. The regeneration zone 83 is provided withbubble caps and down spouts for providing intimate contact between thesolid particles and the regenerating gas. The contaminated solidparticles pass downwardly through the regeneration zone and theregenerating gas passes upward in countercurrent relation thereto.

The regeneration gases leave the top of the regeneration zone throughline 98 and as they carry a certain amount of solid particles with them,it is desirable to pass the regeneration gases through a separatingmeans 88 to recover the solid particles. The separating means 98 may beany suitable construction and is shown in the drawing as a cycloneseparator. More than one separating means may be used if desired. Theregeneration gases pass overhead through line I02 and are removed fromthe system. The separated solid particles are withdrawn from the bottomof the separating means 88 and returned to the upper portion oi theregeneration zone through line 104. If line a: passes directly into thetop of vessel 93 as above described, the air is separated from entrainedsolids in separating means 98.

The solid particles during regeneration in the regeneration zone 93 aremaintained in a fluidized condition during their passage through theregeneration zon'e. Preferably the return pipes 92 and I4 extend belowthe level of the fluidized solid particles on the top plate in theregeneration zone bl.

In the catalytic conversion of hydrocarbons, carbonaceous or organicmaterial is deposited on the catalyst particles. These catalystparticles are regenerated by burning ofl the carbonaceous or organicdeposits. The first part of the regeneratlonis most active and as thereaction is exothermic, it is desirable to prevent the temperature fromrising too high during this portion of the regeneration. Most catalyticsubstances are injured by high temperatures and therefore it isnecessary to control the temperature during regeneration. One way ofcontrolling the temperature is to introduce cooling coils l 06 betweenthe upper plates in the regeneration zone 93. Any suitable heat exchangemedium may be circulated through tubes I".

Steam or other suitable stripping or purging gas is introduced into thebottom portion or purging zone III! of the regeneration zone 93 throughline III! to remove residual oxygen or regenerating gas from the solidparticles in the lower portion of the regeneration zone 93. Theregenerated solid particles are withdrawn from the bottom of theregeneration zone 93 through line 2 having a valve ill. The regeneratedsolid particles are passed through line H8 and introduced into the upperportion or the conversion zone or vessel ll through line ll.

Some of the solid particles are lost from the system by entrainment withthe vapors and gases leaving the separating means and in order tomaintain the amount of solid particles substantially constant in thesystem, fresh solid particles are preferably introduced into the upperportion of the regeneration zone 93 through line II6.

In Figure 4 I have shown another form of apparatus which may be used tocarry out my invention. The vessel I30 is provided with a gas or vaporinlet I32 at the bottom and a vapor or gas outlet I34 at the top. Thevessel is also provided with an inlet pipe I36 extending into the topportion of the vessel for introducing powdered contacting or catalyticmaterial. Near the bottom the vessel I30 is provided with a drawoil oroutlet I38 for withdrawing powdered material which has passed downwardthrough the vessel I30.

The vessel I30 is provided with a bottom distributing plate I42 whichacts to distribute the incoming gas into the bottom portion of thevessel. The vessel I30 is also provided with spaced perforated platesI44, I46, I48 and I52'for supporting fluidized catalyst or solidparticles and for distributing the upfiowing gas or vapor through thefluidized catalyst or solid. The layers of fluidized catalyst or solidI54, I55, I56, I58 and I62 are supported on the respective perforatedplates I42, I44, I46, I48 and I52. The velocity of the vapor or gaspassing upwardly through the vessel I30 aerates or fluidizes the layersof catalyst or solid particles on the perforated plates so that thecatalyst or solid particles or fluidized mass flows like a liquid.

As powdered catalyst or solid material is continuously introduced ontothe top plate I 52 by means of the inlet pipe I36, the level of thefluidized mixture rises and overflows a downfiow pipe I64 which extendsthrough the top perforated plate I52. The downfiow pipe is arranged sothat a portion I66 extends above the perforated plate I52 and anotherlonger portion I68 extends below the perforated plate I52 to a levelabove the next lower perforated plate I48.

The fluidized solid particles flow down the pipe I64 onto the next lowerperforated plate I48 until the mass reaches the level of the pipe I12which carries the fluidized mixture to the next lower perforated plateI46. The downfiow pipe I12 extends through the perforated plate I48 andhas a portion projecting above the plate I48 and another portionprojecting below the plate I48 described in connection with the firstdownfiow pipe I64.

Another downfiow pipe I14 is provided which extends through plate I46and which permits downfiow of the fluidized solid particles to the nextlower perforated plate I44. Another down flow pipe I16 is provided whichextends through the perforated plate I44 and conducts the fluidizedsolid particles to the bottom perforated plate or distribution plateI42. The outlet pipe I38 extends above the perforated plate I42 soithata layer of fluidized solid particles is built up on the plate and whenit reaches the top of the outlet pipe I38, it flows out of the vesselI30.

In the treatment of gases or vapors the gases or vapors are introducedinto the bottom of the vessel I30 and contact the solid particles on theseparate perforated plates as the vapor or gas travels upward. Thevelocity of the vapor or gas is so controlled that the solid particleson the perforated plates are maintained in fluidized condition. Thetreated gas leaves the vessel I30 6 through line I34. In passing upwardthe vapor or gas passes countercurrent to the movement of the solid orcatalyst particles.

The solid particles are maintained on the perfor-ated plates and as thepowdered material is introduced into the top of the vessel onto topplate I52, the fluidized mixture rises above the top I86 of the firstdownfiow pipe I68 onto the nextlower perforated plate I48 from which itpasses through the succeeding downfiow pipes and it is withdrawn fromthe vessel I30 through outlet I38.

The apparatus shown in Figure 4 may be used as either or both reactionvessels shown in Figure 1 of the drawing. While the apparatus may beused for the catalytic cracking of hydrocarbons, it is especiallyadapted for the regeneration of catalyst particles which have becomecdated with carbonaceous material. catalyst particles containing themost carbonaceous material are introduced into the top of the vessel I30where the upfiowing gas has a low oxygen concentration. It is easiest toremove a large amount of the carbonaceous material in the first .part ofthe regeneration and by limiting the amount of oxygen, the regenerationis controlled to prevent excessively high temperatures.

When the catalyst particles arrive near the bottomof the vessel I30,most of the carbonaceous material has been burnt oil and it is difflcultto remove the remaining traces of carbonaceous material. The catalystparticles in the lower portion of the vessel I30 are contacted with gascontaining a high oxygen concentration and the removal gftthe remainingcarbonaceous material is facilia ed.

In Figure 4 the bottom of each downfiow pipe is about on a level withthe top Of the next lower downfiow pipe. For example, the bottom ofinlet pipe I36 is about on a level with the top I66 of downfiow pipeI64. If desired, the level of the fluidized solid particles on eachperforated plate may be raised by using longerpipes and having the topsthereof extending above the bottoms of the draw-oil? pipes. For example,with the inlet pipe I36 as shown, a longer tube I64 may be used havingits lower end positioned as shown whereas the upper portion I66 wouldextend above the position shown. In this way a thicker layer offluidized solid particles would be obtained and the level of the layerwould extend above the outlet end of inlet pipe I 36. The remainingdownfiow pipes may be similarly arranged to increase the deptth ofthe-layer o fluidized particles on each pla e.

The above modification of Fig. 4 is shown in Fig. 5 wherein the sameparts are designated by the same reference characters used in Fig. 4. InFig. 5 the downfiow pipe I64 has its upper end I at a higher level thanthe bottom I82 of inlet pipe I36. Similarly the next lower downflcw pipeI12 has its upper end I84 above the bottom I86 of downfiow pipe I64. Thenext lower downfiow pipe I14 has its upper end I88 above the bottom I90of downfiow pipe I12. The next lowerdownfiow pipe I16 has its upper endI82 above the bottom I84 of downfiow pipe I14. Outlet pipe I38 has itsupper end I96 above the bottom I98 of downfiow pipe I 16.

With the apparatus shown in Fig. 5, the level of the fluidized solidparticles on each plate is raised by using longer pipes and having thetops thereof extending above the bottoms of the draw-off pipes as aboveset forth in the description of the modification of Fig. 4.

76 In the catalytic cracking of hydrocarbons, gas

It will be seen that the.

7 oil vapors at a temperature of about 850 1''. to 1000 F. areintroduced into the reaction vessel or zone ill through line II. Thecatalyst particles at about the same temperature or as high as 1200 F.are introduced into the upper porrtion of the reaction zone l throughline H. The catalyst is in finely divided form and is of such a sizethat substantially all of the catalyst particles will pass through 50 to400 mesh or finer of the standard series. As a catalyst, any suitablecatalytic material may be used such as acid activated bentonite clays,synthetic gels containing silica and alumina or silica andmagnesia, etc.

' During passage through the reaction zone or vessel ID, the oil vaporsare intimately contacted with the catalyst particles and are convertedto lower boiling hydrocarbons. The products of conversion pass overheadand are preferably passed through line 58 to a fractionating system forseparating desired motor fuel from higher boiling constituents.

During the conversion, the catalyst particles become coated withcarbonaceous material and as the catalyst particles pass into thestripping section of the vessel Ill, residual volatile hydrocarbons areremoved. The catalyst particles with the remaining carbonaceous depositsare introduced into the top portion of the regeneration zone. Thecatalyst particles are at a temperature of about 800 F. to 1000 F. Inthe regeneration zone the contaminated catalyst particles are intimatelycontacted with air and the carbonaceous material is burned from thecatalyst particles, During regeneration of acid treated bentonite clays,the temperature is maintained below about 1200 F. to prevent injuring oithe catalyst parnomenon can be utilized in many reactions where gasesreact with or treat solids such as chlorination of solids, drying ofsolids. roasting of ores, partial oxidation or carbonization of coal,absorption of gases by solids, gas purification, production of ironcarbonyl from iron oxide and carbon monoxide and the like.

The catalyst particles while passing through the reaction zone in andthe regeneration zone 93 are maintained in a fluidized condition so thatthey fiow like a liquid. In order to maintain the catalyst particles influidized condition, the velocity of the vapors passing upward inreaction zone II and the velocity'of the gas or gases passing upwardlyin regeneration zone 93 are about 0.5 to 3 feet per second. By havingthe contacting means within the vessels Ill and 83, better heat controlof the interior of the reacting mass is possible. By adding or removingticles or sintering thereof. The regenerated catalyst particles passthrough the stripping zone or purging zone 10'! in the regeneration zone93 and are then withdrawn from the bottom portion of the regenerationzone through line I H. The regenerated catalyst particles at atemperature of about 850 1'. to 1200 F. are returned through lines H6and I4 to the upper portion of the reaction zone or vessel ID foranother conversion operation.

One of the important features of the invention is the counterflow heatexchange of gases and solids which may be employed for heating orcooling either. For instance, in the regeneration in vessel 93 hotproducts of combustion at about 1100 F. and deficient in' oxygen heatcatalyst at about 900 F. and distill ofi residual hydrocarbons,decreasing the air requirements for regeneration. Then, in the topsection the high carbon catalyst is burnt in the presence of low oxygenconcentration air. In the bottom section the catalyst lean in carbon isburnt in the presence of gas high in oxygen concentration, almost pureair. Better temperature control of the surface of the catalyst duringbuming, better temperature distribution in the vessel and less time forburning results from having the high carbon catalyst burn in low oxygenconcentration gas and low carbon catalyst burn in high oxygenconcentration gas rather than a fixed concentration of either reactantin the vessel.

This is an example of the utility of counterflow powder and gas contactvessel where concentration gradients exist, the gradients being bothpositive and negative so that the mass action efiect in the desiredreaction is more or less even throughout the vessel. Such a pheheat inthe heat transfer tubes, any temperature gradients in the tower may bemaintained. My process is also an improvement of other vessels which donot 7 contain any contacting means in that channelling is avoided andbetter agitation and'contact are obtained between the solid particlesand the gases or vapors.

While two forms of vessel have been shown forthe reaction andregeneration zones, it is to be understood that other forms of apparatussuch as packed towers, disc and doughnut towers may be used to provideintimate contact between the solid particles, gases or vapors, etc,while maintaining the solid particles in fluidized condition so thatthey flow down through the tower or vessel as a fluidized mass. Myinvention is not to be restricted to the catalytic cracking ofhydrocarbons and may be used for other catalytic reactions as forexample the synthesis of hydrocarbons from carbon monoxide and hydrogen,

hydrogenation, dehydrogenation, alkylation, isomerlzation,polymerization, etc.

The invention lends itself to flexibility in adding or removing gases orcatalyst from any portion of the reaction vessel. For instance, catalystmay be added or removed from different plates, and, likewise, gases maybe added or removed from eachplate, the latter requiring catalystseparating means to return the catalyst .to the vessel. In themodification shown in Fig. '5, line 202 is shown having valved branchlines 204, 206 and 208 for adding catalyst or solid particles to thebeds I58, I, and I, respectively, of vessel I30. Another line 2"! isshown having valved branch lines 24!, 2M and 216 for removing catalystor solid particles from beds I", I56 and lit, respectively, from vesselB0.

The invention is not to be restricted to the showing in the drawing andthedetails given in the description as various modifications and changesmay be made without departing from the spirit of the invention.

This case is filed as a division or my application Serial No. 410,525,filed September 12, 1941, on "Treating hydrocarbon fluids" now 0.S.-Pat-' ent No. 2,444,990, dated July 13, 1948.

I claim:

1. An apparatus for contacting finely divided particles with a gaseousagent comprising an enlarged vertical vessel, a plurality of perforateddecks mounted in vertically spaced relation within said vessel, aseparate conduit extending through each of said decks, the upper end ofeach of said conduits terminating below the superadjacent deck and theiowerend of each of said conduits terminating above the subadiacentamass deck but not higher than the upper end of the conduit extendingthrough said subadjacent deck, a tubular member communicating with theupper end of said vessel for introducing finely divided solids to becontacted on to the uppermost perforated deck, a second tubular memberextending through said lowermost deck and terminating below the decksuperadjacent thereto for removing finely divided solids from saidlowermost deck, a conduit communicating with the lower end of saidvessel for introducing a gaseous agent therein below said lowermostdeck, a second conduit communicating with the upper end of said vesselabove the uppermost deck for removing gaseous agent from said vessel,whereby the gaseous agent may pass upwardlythrough the perforations insaid decks,at a velocity suf flcient to support said finely dividedsolidson said decks and to maintain said solids in a fluid, quasi-liquidstate and continuous introduction of finely divided solids on theuppermost deck will cause said fluidized particles to overflow throughsaid conduits from one deck to the next subadjacent deck.

2. An apparatus for'contacting finely divided particles with a gaseousagent comprising an enlarged vertical vessel, a plurality of perforateddecks mounted in vertically spaced relation within said vessel, aseparate conduit extending through each of said decks, the upper end ofeach of said conduits terminating below the superadjacent deck and thelower end of said conduit terminating above thesubadjacent deck andlower than the upper end of'tlie conduit extending through saidsubadjacent'ideck, a tubular member communicating-with the upper end ofsaid vessel for introducing finely divided solids to be contacted withsaid gas, a secondcondult extending through the lowermost deck andterminating-below the deck superadiacent thereto for removing finelydivided solids from the lower most deck, a conduit for introducing agaseous agent into said vessel below said lowermostneck, a conduitcommunicating with the upper end of said vessel above said uppermostdeck for removing the gaseous agent from said vessel, whereby thegaseous agent may pass upwardly through the perforations in said decksat a valuetion in the lower portion a: said vessel below the means forintroducing vaporous reactant, a conduit extending through each of saiddecks except the lowermost deck, the upper end of each of said conduitsterminating below the superadjacent deck and the lower end of each ofsaid conduits terminating above the subadjacent deck but not higher thanthe upper end of the conduit extending through the said subadjacentdeck, means for introducing a gas below the lowermost deck in saidvessel and a conduit for withdrawing finely divided solid materials fromthe lowermost deck in said vessel, the inlet to said last-named conduitbeing below the next to lowermost deck in the vessel but not below thelower end of the conduit extending through the said next to lowermostdeck.

4. A conversion system which comprises a unitary apparatus including asubstantially vertical vessel comprising an upper reaction section and alower stripping section, a plurality of perforated decks mounted invertically spaced relation within the upper reaction section of saidvessel, a conduit extending through each of said decks, said conduitsextending a substantial distance above and below the perforated deckthrough which it extends, the upper end of each of said conduitsterminating below the superadjacent deck and the lower end of each ofsaid conduits terminating above the subadjacent deck but below the upperend of the conduit extending through the said subadjacent deck, meansfor introducing vaporous reactant below the lowermost perforated deck insaid reaction section, means for introducing finely divided solidmaterials to the topmost perforated deck in said vessel, means forremoving vaporous products from the top of said vessel, a plurality ofperforated decks mountity sufficient to maintain said solids in a fluid,

quasi-liquid state and continuous introduction of finely divided solidson the uppermost deck will cause said fluidized solids to overflowthrough said conduits to the next subadjacent tray.

3. A conversion system which comprises a unitary apparatus including asubstantially vertical vessel comprising an upper reaction section and alower stripping section, a plurality of perforated decks mounted invertically spaced relation rials to the topmost perforated deck in saidV6553], means for removing vaporous products from the top of saidvessel, a plurality of perforated decks mounted in vertically spacedrelaed in vertically spaced relation in the lower portion of said vesselbelow the means for introducing vaporous reactant, a conduit extendingthrough each of said decks except the lowermost deck, the upper end ofeach of said conduits terminating below the superadjacent deck and thelower end of each of said conduits terminating above the subadjacentdeck but below the upper end of the conduit extending through the saidsubadjacent deck, means for introducing a gas :below the lowermost deckin said vessel and a conduit for withdrawing finely divided solidmaterials from the lowermost deck in said vessel, the inlet to saidlast-named conduit being below the next to lowermost deck in the vesseland above the lower end of the conduit extending through the said nextto lowermost deck.

5. A conversion system which comprises a substantially vertical vessel,a plurality of perforated decks mounted in vertically spaced relationwithin said vessel, a conduit extending through each of-said decksexcept the lowermost one, each of said conduits extending a substantialdistance above and below the perforated deck through which it extends,the upper end of each of said conduits terminating below thesuperadjacent deck and the lower end of each of said conduitsterminating above the subadjacent deck but not higher than the upper endof the conduit extending through said subadjacent deck, means forintroducing a gas below the lowermost deck in the vessel, means forremoving vaporous products from the top of said vessel, means forintroducing finely divided solid materials to the topmost deck in saidvessel and a conduit for withdrawing finely divided solid materials fromthe lowermost deck in said vessel, the inlet to l 1 said last-namedconduit being below the next to lowermost deck in the vessel but notbelow the lower end of the conduit extending throush said next tolowermost deck.

6. A conversion system which comprism a substantially vertical vessel, aplurality oi periorated decks mounted in vertically spaced relationwithin said vessel; a conduit extending through each of said decksexcept the lowermost one. each of conduits extending a substantialdistance above and below the perforated deck through which it extends.the upper end 01' each of said conduits terminating below thesuperadiacent deck and the lower end of each of said conduitsterminating above the subadiacent deck but below the upper end or theconduit extending through said subadiacent deck, means for introducing agas below the lowermost deck in the vessel, means for removing vaporousproducts from the top of said vessel, means for introducin'g finelydivided solid materials to the W deck in said vessel and a conduit forwithdrawing finely divided solid materials from the lowermost images!deck in said vessel, the inlet to said last-named conduit being belowthe next to lowermost deck in the vessel and above the lower end of theconduit extending through said next to lowermost deck. CHARLES E.HEBDIINGER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

1. AN APPARATUS FOR CONTACTING FINELY DIVIDED PARTICLES WITH A GASEOUSAGENT COMPRISING AN ENLARGED VERTICAL VESSEL, A PLURALITY OF PERFORATEDDECKS MOUNTED IN VERTICALLY SPACED RELATION WITHIN SAID VESSEL, ASEPARATE CONDUIT EXTENDING THROUGH EACH OF SAID DECKS, THE UPPER END OFEACH OF SAID CONDUITS TERMINATING BELOW THE SUPERADJACENT DECK AND THELOWER END OF EACH OF SAID CONDUITS TERMINATING ABOVE THE SUBADJACENTDECK BUT NOT HIGHER THAN THE UPPER END OF THE CONDUIT EXTENDING THROUGHSAID SUBADJACENT DECK, A TUBULAR MEMBER COMMUNICATING WITH THE UPPER ENDOF SAID VESSEL FOR INTRODUCING FINELY DIVIDED SOLIDS TO BE CONTACTED ONTO THE UPPERMOST PERFORATED DECK, A SECOND TUBULAR MEMBER EXTENDINGTHROUGH SAID LOWERMOST DECK AND TERMINATING BELOW THE DECK SUPERADJACENTTHERETO FOR REMOVING FINELY DIVIDED SOLIDS FROM SAID LOWERMOST DECK, ACONDUIT COMMUNICATING WITH THE LOWER END OF SAID VESSEL FOR INTRODUCINGA GASEOUS AGENT THEREIN BELOW SAID LOWERMOST DECK, A SECOND CONDUITCOMMUNICATING WITH THE UPPER END OF SAID VESSEL ABOVE THE UPPERMOST DECKFOR REMOVING GASEOUS AGENT FROM SAID VESSEL, WHEREBY THE GASEOUS AGENTMAY PASS UPWARDLY THROUGH